W114 250CE Cilinder Head Gasket leak

Dear "Schrauber" mechanics,


I do have a water leakage of my cilinder head gasket and am now busy to fix it. 

I will have some more questions coming weeks, hope you people can support me.

Below the leakage itself and my first question

1) Is it a good idea to clean my cast aluminium intake manifold, the inside and outside with warm water and Dasty (Classic Fettlöser).

Greetings Marc

 

 
 
 

Hi all,

2) below there is a picture of the right side of the engine. There i see no drips marks at all. My question is if you heave a leakage is it always at one side of the engine and if yes what is the reason behind it. Or is it always just random. 

Greetings Marc

 

Hi All,

3) I checked my camshaft for all cam surfaces. They all look fine except cam nr 1 (the one that is actuating the exhaust valve for cilinder 1). Is this a problem? I can feel the scratches with my finger nail. I do know its hard to judge from a picture but pls any advice is welcome. And what could be the cause for this only one cam? A blocked pinhole in my oil line ?

Greetings Marc

I added a new picture cam and rocker.

 



 

Hi Marc,
the camshaft is hardened only on the surface.
If there is some wear, the hardened surface is gone, the wear will increase until most of the cam is gone.
I think I can see some wear... you have to measure the hight of this cam and compare it with the others.

- There are companies specialized in rebuilding camshafts. Maybe this could be an option.

- Cylinder-head-gaskets can leak oil or water or oil and water to the outside or inside of the engine.. One has to check the surface and the shape of the block and the head and check for internal leaks before installing a new gasket. When there is leakage, very often not only the gasket is brittle.

Regards
Norbert

...your engine looks like someone renewed the head gasket and forgot to retighten the screws at least one time ! 

If you can feel the scratches on the camshaft it needs to be replaced soon !

Hi Norbert and Christian,

Thanks for your quick replies. 
I checked today to see if there were any visible blockages in the oil supply pipe near the oil spray holes for each cam for cilinder 1, but everything looked fine from the outside. (Later i will check this with air pressure when everything is taken apart).

I also measured the valve clearance for the exhaust cam on cylinder 1, and it was 0.2 mm, exactly as specified in the manual. I heard yesterday that, in addition to clogged oil supply channels, a lack of clearance can be another cause of cam wear.


Regarding Christian's comment about re-tightening : the engine has run well for 28 years now, even though I don't think I've driven it more than 500 km a year on average. However, if I recall correctly, we followed the (c) Autodata Limited specifications at that time saying a three-stage process of 40, 60, and then 80 Nm. I now see in the 1972 edition of the manual that the check should also be performed with the engine warm; I do not recall doing that.

Besides the specification in the below picture any more recommendations with respect to torque? Maybe after 1000 km a re-check, cold or warm?

Greetings Marc

 

 

 

...warm after 300-800 KM, like written in Mercedes Workshop Manual !

Hi everyone,

I found the amount of rotational play in the so-called intermediate shaft "Zwischenwelle blue and green"" to be quite significant, so I tried to measure it.
To do this, I 3D-printed a plastic pointer and inserted it into the slot of the green vertical output shaft. Then, using a small hex key, I turned the output shaft fully to the left and then to the right. The total angular movement was approximately 3.5 degrees.

5) Is this 3.5 degrees a problem when the engine is idling? I was thinking, If there are slight variations in drive torque form the motor, the distributor will take up this slack/play, resulting in variations in spark timing. Or am I splitting hairs? Is the play always pushed to one side.

Looking forward for you opinions.

Regards, Marc

ps today i tried to make some pictures of the "Zwischenwelle set" the area's of contact.